You should understand that the carat weight is just one of the 4 C’s that mainly affect the price of a diamond, color, clarity, and cut being the other three. Besides, carat does not proportionately affect 1-carat diamond ring prices. For instance, the collective price of three 1 carat diamonds will be much less than a 3 carat stone. In fact, the price of diamonds goes up with the number of carats.
Generally, the cost of a 1-carat diamond ring in the US ranges from $3,000 to $27,500. As said, this huge variation in the price range is because of the other three factors – color, clarity, and cut. A round brilliant cut diamond of IF clarity and D color will be a very expensive purchase, but it will be much affordable if you go for an oval cut stone of VS2 clarity and H color – the carat weight in both instances still being the same 1 carat.